Stencil sheet



Patented Oct. 26, 1926.

UNITED STATES RICHARD LANT, OF VIENNA, AUSTRIA,

The present application is a division of my co-pending application,Serial No. 601,415, filed November 16, 1922 for stencilsheet.

According to my invention the manufacturing of a protein stencil sheet,whichwithout being hygroscopic or including water and Withoutpreliminary moistening can be used in a; perfectly dry state forpreparing the stencil, is realized by adding to the coating masshydro-carbon material to such an amount, that in preparing the stencilin the typewriting machine by the impact of the type only those parts ofthe coating mass are removed, which are directly struck by theprotruding lines of the steel type forming the characters, whilst theinterstitial spaces bordered all around by the 'lines forming thecharacters will not be stamped out. The hydrocarbon material employed isofan oleaginous character and for the purposes of the invention mineraloil hydrocarbons adapted for use as lubricants and possessing a highboiling point ma be used. For diminishing the brittleness oi thecoagulated protein to such a degree, that stencil sheets may be obtainedefficiently operating without moistening, the hydrocarbon containingmaterial has to amount to more than the weight of the protein containedin the coating mass. The hydrocarbons may be added to the solution ofthe protein in the form of an emulsion or of a suspension or of acolloidal solution. The coating of the open porous base, preferablypaper, is effected either by dipping it into the mixed solution or elseby spreading the solution on it by means of a brush or sponge.

After the coating has been dried, the sheet is drawn through a strongsolution of formaldehyde for the purpose of coagulating the protein andthen dried again.

What I claim is:

1. A stencil sheet comprising a base of open porous material coated witha composition, substantially free from water and hygroscopic materials,consistingessentially of a gelatinized organic colloid, deposited froman aqueous medium, and an oleaginous hydrocarbon material, saidoleaginous hydrocarbon material being present in proportion suflicientto maintain the composition permanently in a state in'which it may bePATENT OFFICE ASSIGNOR, BY MESNE ASSIGNMENTS, TO D. GESTETNER, LIMITED,OF-LONDON, ENGLAND, A CORPORATION.

STENCIL SHEET.

No Drawing. Original application filed November 16, 1922, Seria1 No,601,415, and in Austria October 11,

i 1922. Divided and this application Tiled. December 21, 1923. SerialNo. 682,089.

stencilized when substantially free from moisture.

2. A stencil sheet comprising a base of open porous materialcoated witha composition consisting essentially of a protein and an oleaginoushydrocarbon material, said oleaginous hydrocarbon material being presentin a proportion suflicient to maintain the composition permanently in astate in which it may be stencilized when substantially free frommoisture.

3. A stencil sheet comprising a base of open porous material coated witha composition consisting essentially of an emulsion of a gelatinizedorganic coloid, deposited from an aqueous medium, and a proportion of anoleaginous hydrocarbon material suflicient to maintain the compositionpermanently in a state in which it may be stencilized when substantiallyfree from moisture.

a. A stencil sheet comprising a base of open porous material coated witha composition consisting essentially of an emulsion of a gelatinizedprotein and an oleaginous hydrocarbon material in a proportionsulficient to maintain the composition permanently in a state in whichit may be stencilized when substantially free from moisture.

5. A stencil sheet comprising a base of open porous material coated witha composition substantially free from water and hygroscopic material andcontaining a gelatinized organic colloid deposited from an aqueousmedium and a suflicient proportion of mineral hydrocarbon-containingmaterial of high boiling point adapted to diminish the brittleness ofthe gelatinized colloid and to maintain the stencil sheet indefinitelyin a condition in which it may be stencilized-by pressure or impactwithout the application of moisture.

6. A stencil sheet comprising a base of open porous material coated witha composition cons sting essentially of an emulsion of a gelatinizedorganic colloid deposited from an aqueous medium and a viscous mineraloil present in a proportion sufiioient to maintain the compositionpermanently in a state in which it may be stencilized when substantially free from moisture.

7. A stencil sheet comprising a base of open porous materialcoated witha composition consisting essentially of an emulsion ncluding agelatinized protein deposited irom an aqueous medium and a mineral 011.of lubricant character in a proportion sufficient to maintain thecomposition permanently in a state in which it may be stenci1ized whensubstantially free from moisture.

8. A process for the manufacture of stencil sheets adapted forstencilization by pressure comprising coating a base of open porousmaterial with a composition consisting essentially of a gelatinizingorganic colloid solated in an aqueous med um and an oleaginoushydrocarbon material of high boiling point, sufficient to mainta n thecomposition permanently in a state in which 1t may be stencilized whensubstantially tree from moisture, and rendering the coating compositionsubstantially air dry.

9. The process for the manufacture of stencil sheets adapted forstencilizatlon by pressure, which comprises coating a base of openporous material with a composition consisting essentially of a proteinsolated in an aqueous medium and a proportion of an oleaginoushydrocarbon material of high boiling point, sufficient to maintain thecomposition permanently in a state in which it may be stencilized whensubstantially free from moisture, and rendering the coating compositionsubstantially air dry.

10. A process for the manufacture of stencil sheets adapted forstencilization by pressure in a dry state which comprises coating a baseof open porous material with an aqueous disperse system including aprotein and a light and viscous mineral oil in a state of colloidaldispersion, said light and viscous mineral oil being present in aproportion suflicient to maintain the composition permanently in a statein which it may be stencilized when substantially free from moisture,drying the coating and hardening the protein.

In testimony whereof I have aflixed my signature.

RICHARD LANT.

